The present invention relates to a shade matching system for selecting the shade of an artificial teeth and crown restoration.
According to a conventional method a shade guide with a stick for an artificial teeth and crown restoration (simply referred to as a "shade guide" hereinafter) has been used alone or used while the stick of the shade guide was inserted into a holder. This embodiment is adopted for the sake of preventing damage at selling or transportation. According to this conventional method mismatching in shade between the natural tooth and the artificial teeth which was actually fixed in a mouth has been often caused owing to a large error generated when the shade was examined by shade guides in the mouth of a patient.
Conventional holders are liable to cause mismatching in the shade because of difficulty of adjusting the shade due to contrast effect of color caused by the color reflection of the background or the stick when shade of the teeth is examined in patient's mouth, when there is a space between adjacent shade guides or between the shade guides and the holder. Particularly, if there is a space at the neck of teeth, it was difficult to determine a correct shade due to the contrast effect of shade by the influence of color of the background and the stick when comparing the shade guide with natural teeth which is in contact with the gingiva.